Chapter 1. Introduction

This book is intended to cover several topics people programming within the SpecTcl histogramming framework might need. The intended audience are those who might be tailoring SpecTcl to analyze the data from a specific experiment from the NSCLDAQ as well as those who may want to go further. This guide is intended to be used in conjunction with the programming reference manual which provides detailed class reference information for the key classes.

Topics we are going to consider in this manual include:

The SpecTcl processing model.

Which covers the processing model used by SpecTcl. This will be covered in a bit greater detail than in the user guide. Understanding this model, and where to attach your code to it can be important to following the path of least resistance in accomplishing your programming goals.

The SpecTcl event processing pipeline.

The event processing pipeline is the set of objects that transform raw events into parameters that SpecTcl processes. We'll take a look at this and describe how to write event process pipeline elements as well as how to prepare SpecTcl to anlyze filtered data. Along the way the SpecTclAPI object will be introduced. It provides stable interfaces to several important subsystems of SpecTcl

The SpecTcl event sink pipeline.

The event sink pipeline takes over where the event processing pipeline leaves off. It performs all processing on the unpacked event. The built in processing includes Histograming and processing any filters that are active. You can, however, hook your own code to the event sink pipeline.

libTcl++ and adding commands to SpecTcl

SpecTcl uses the Tcl scripting language as its base command language. There are cases where adding a compiled command to SpecTcl is useful. This chapter introduces the Tcl++ C++ wrapping of the Tcl interpreter and how to use it to add commands and interface with other interpreter elements.

Extending SpecTcl spectrum file formats

The SpecTcl sread and swrite commands write spectra to file. They have a -format option that determines the format in which spectra are written. This chapter describes how to add spectrum formats to the swrite and sread commands.

Extending SpecTcl's filter file formats

The format of files written by SpecTcl filters is extensible. In this chapter we'll show how to extend the set of formats available.

Extending the set of SpecTcl fit types.

The SpecTcl fitting subsystem allows you to add additional fit types. In this chapter we'll show how to add a new fit-type to SpecTcl.

Interfacing SpecTcl with data from other data acquisition systems.

SpecTcl is data acquisition system neutral. This chapter will explore how this is managed and describe how to extend SpecTcl so that it can handle data from another data acquisition system.

Dynamic processing pipelines

Describes new features for SpecTcl 5.1 which allow you to dynamically alter the event processing pipeline.